Solve for $t$ : $-10 + t = -25$
Explanation: Add $10$ to both sides: $ \begin{eqnarray} \\ -10 + t &=& -25 \\ \\ {+10} && {+10} \end{eqnarray} $ $ \begin{eqnarray} \hphantom{-10 + t} &\hphantom{=}& \hphantom{-25} \\ t &=& -25 {+ 10} \\ \end{eqnarray} $ Simplify. $ t = -15$